The title compounds are useful as intermediates in making polymeric peptizers as described in U.S. Pat. No. 3,615,624 (Table II) and as intermediates in making pharmaceuticals such as Ranitidine and others as described in U.S. Pat. Nos. 4,128,658, 4,169,855, 4,255,440 and 4,279,819. All of these patents are hereby incorporated by reference.
This class of compounds may be made by the method of U.S. Pat. No. 3,615,624 which reacts ethyleneimine with 2-furylmethylthiol (Table 2, No. 4), however, ethyleneimine is highly toxic, and difficult to work with commercially.
This class of compounds may also be made by reacting furfurylmercaptan with bromoethyl phthalimide and then removing the phthalic acid moiety by reaction, for example, with hydrazine hydrate as taught in U.S. Pat. No. 4,279,819 (Column 7). However, this requires two-steps with purifications and expensive reagents which are lost as by-products.
U.S. Pat. No. 4,086,273, which is hereby incorporated by reference, discloses a reaction of an aliphatic mercaptan with a 2-oxazoline in the presence of a transition metal catalyst. This patent teaches that the aliphatic mercaptans do not give good yields of the adduct without use of the catalyst. If the product is to be used as a pharmaceutical, it should be carefully purified of metal residue. Any residue may have an adverse effect on further reactions or may ultimately show up in the product which is undesirable if the metal is at all toxic.